[Intel-gfx] [PATCH 07/10] drm/i915: print Gen5+ CPU poison interrupts

[Jesse Barnes]

On Fri,  8 Feb 2013 17:35:18 -0200
Paulo Zanoni <przanoni at gmail.com> wrote:

> From: Paulo Zanoni <paulo.r.zanoni at intel.com>
> 
> On ILK/SNB all we need to do is to enable the "poison" bit, but on
> IVB/HSW we need to enable the CPU error interrupt register, which is
> responsible not only for poison interrupts, but also other things.
> This includes the "unclaimed register" interrupt, so on the IVB irq
> handler we now need to: (i) check whether the interrupt was triggered by an
> unclaimed register and (ii) mask the error interrupt bit so we don't
> risk generating "unclaimed register" interrupts form inside the
> interrupt handler.
> 
> Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
> ---

OTOH there's nothing the user can do about it... so we might do a
WARN_ONCE or something here instead.  But even then, I'm not sure
there's much *we* can do about these, as they indicate a corruption in
the communication between the CPU and PCH.

-- 
Jesse Barnes, Intel Open Source Technology Center